docs: def _symbols():
      """(Lazy)load list of all supported symbols (sorted)
  
      Look into `_data()` for all currency symbols, then sort by length and
      unicode-ord (A-Z is not as relevant as ֏).
  
      Returns:
          List[unicode]: Sorted list of possible currency symbols.
      """
      global _SYMBOLS
      if _SYMBOLS is None:
          tmp = [(s, 'symbol') for s in _data()['symbol'].keys()]
          tmp += [(s, 'alpha3') for s in _data()['alpha3'].keys()]
          tmp += [(s.name, 'name') for s in _data()['alpha3'].values()]
          _SYMBOLS = sorted(
              tmp,
              key=lambda s: (len(s[0]), ord(s[0][0])),
              reverse=True)
  
      return _SYMBOLS